The present invention relates to a new and improved cable structure comprising a cable provided with a cable sheath or jacket in the form of a flexible corrugated or undulated tube.
Such type cable structures are particularly used in above-ground or building structures and underground structures as tensioning cables. The cable itself is formed of a wire, or however stranded wires, and a number of wires or stranded wires are assembled together into a cable.
Cable sheaths in the form of flexible corrugated or undulated tubes are already known to the art. Such sheaths or jackets conventionally consist of an undulated tube formed of metal which can be surrounded by a corrosion protective layer, for instance bitumen. The entire structure can be surrounded by a thin outer jacket formed of plastic.
Such cable sheaths normally form a corrosion protection for the actual cable. The cable does not directly bear at the sheath inner wall. In the intermediate space between the sheath and the cable there can be incorporated for instance additional protective material, such as for example a protective grease mass.
Cables provided with such type sheaths are presently, whenever possible, already wound-up at the factory upon large drums and transported to the construction site. Also during such transport care must be taken to ensure that the sheaths are not damaged, since otherwise their actual effect is impaired.
Also during operation cables equipped with such sheaths are subjected to the most different loads. The actual tensile load does not have any negative effect upon the sheath or jacket. If, however, during operation such cable begins to oscillate, something possible for instance in the case of anchoring cables for floating platforms and the like, then there are required special protective measures for the cable surrounded by the corrugated tubes.